Land Preparation Techniques Research Articles

The effect of crop insurance on the financial risk of smallholder rice farmers in Cameroon

This study examined the effect of crop insurance on the financial risk of smallholder rice farmers in the grass field of Cameroon. Panel data from 76 Smallholder rice farming groups from 2019-2022 was used, while the Panel-corrected standard error technique was used for estimation. The results revealed that crop insurance captured using inputs (fertilizers, herbicides, and treated seeds) and land preparation had a positive and statistically significant effect on financial risk. These results validate the risk balancing hypothesis for smallholder rice farmers. Control variables like Farm size and labour had a positive and statistically significant effect, while training cost and buying price had a negative and statistically significant effect on financial risk. The results therefore, indicate that smallholder rice farmers need to adopt crop insurance practices such as use of quality farm inputs and better land preparation techniques in order to manage financial risk.

Zero-Burning Policy in Land Preparation: Social Changes and Its Impact on Communities and the Environment

In Indonesia, forest and land fires have become an annual occurrence, with devastating effects. Following major fires in 2015, the government implemented policies restricting the use of fire in land preparation. This policy has affected the livelihoods of traditional farmers who still use fire for land clearing. The research aims to analyze the social changes that have occurred among traditional farmers as a result of the policy to ban burning in land preparation, and to assess its impact. The study was undertaken in Pulang Pisau Regency (Central Kalimantan) and Ogan Komering Ilir Regency (South Sumatera). Findings reveal two types of social transformation processes, namely, changes in agricultural commodities and changes in livelihoods. In general, fire policy restrictions in land preparation improved peatland ecosystems, but has had a detrimental impact on some rural communities living around peatlands. To anticipate these effects, the government promoted no-burn land preparation techniques and initiated a new paddy field construction scheme. However, both were less successful due to local resistance for their unsuitability in the local context.

Management of coffee agroforestry systems: lessons learned from a social forestry program in West Java, Indonesia

Indonesia has a long history of social forestry (SF). The essence of this scheme is to involve the community in managing state forests. The agroforestry system is the main choice, with trees already on forest land. The combination of trees and crops provides an alternative livelihood for the community. Coffee plants are one of the choices for undergrowth plants. This study aims to explain the management of coffee agroforestry in social forestry programs. The method used was direct observation in the field combined with a focus group discussion involving six Forest Village Community Institutions (LMDH) with 15 respondents for each LMDH. The results showed that farmers mainly chose coffee because it was shade-tolerant, allowing it to grow well under tree stands. Coffee management in SF with an agroforestry system differs from a monoculture cultivation system in terms of spacing, number of coffee plants per hectare, land preparation techniques, planting, maintenance, and productivity. The government can encourage the management of coffee agroforestry systems in state forests through social forestry schemes by providing training and facilities to increase the added value of coffee in advanced products, providing access to production facilities, capital, and markets, and institutionally strengthening farmer groups.

USING THE ACTIVITY-BASED APPROACH TO FACILITATE THE TOPIC ‘SUSTAINABLE LAND PREPARATION TECHNIQUES’ AMONG STUDENT TEACHERS: A CASE STUDY IN BAGABAGA COLLEGE OF EDUCATION

The study assessed using the activity-based approach to facilitate the topic ‘sustainable land preparation techniques’ among student teachers. Action research was adopted for the purpose of the study. The study used three achievement test research questions as a guide and adopted the case study design. The topic was previously taught through a traditional lecture-based format which revealed that student engagement was poor and learning was limited. Student engagement was measured through a questionnaire and case study. The instrument used to collect data for the study was a questionnaire. One hundred and twenty-two agriculture/Home Economics students’ teachers of the 2022/2023 academic year were used. For the encouragement of student understanding, a wide variety of activities were used. These activities included think-pair share, role plays, presentations, self-reflection, and written submissions. The findings reveal that the overall performance of the students after the intervention showed they were able to differentiate between the two concepts. The findings also revealed that an activity-based approach enhanced student teachers' knowledge of the topic of sustainable land preparation techniques and motivated student teachers not to perceive the topic of sustainable land preparation techniques to be difficult. The study concluded that Student teachers' learning was achieved through the completion of a series of activities based on different topics covered in sustainable agriculture practices.

Trends in Production of Pulses and Oilseeds Over Last Two Decades in Eastern India

"India is a major producer and consumer of a wide variety of pulses and oilseeds but still struggles to achieve self-sufficiency due to the growing disparity between demand and supply. The present study has made an attempt to compare and disseminate trends in acreage, production, and productivity of pulses and oilseeds over the last two decades (1999-2000 to 2018-2019). Regarding the computation of growth and instability, a modified exponential production function is fitted, and to judge the overall change in production, a decomposition of the trend in area and yield over two decades has been performed. Bihar and West Bengal stand out as the primary producers of pulses, while rapeseed and mustard take the lead among oilseed crops, followed by sesame. Odisha uniquely contributes to groundnut production, while linseed has become integral to West Bengal’s overall oilseeds output. To enhance production in these states, implementing HYV seeds, proper land preparation techniques, and adopting paira cropping in rice-fallow situations can significantly boost the current status of pulses and oilseeds in the eastern India."

Evaluation of Different Land Preparation Techniques for Preparing Medium Textured Soil in Rice Production under Agro-Ecological Conditions of Sheikhupura-Pakistan

Tillage is an important factor affecting different soil properties and crop yields. Tillage relates to applying forces to soil using different implements for preparation of a proper seed bed. For rice crop, land preparation is a rigorous and time consuming operation that needs special attention for preparing a puddled soil condition to transplant the weak and tender rice seedlings. A field experiment was established under agro-ecological conditions of Sheikhupura to evaluate different land preparation techniques during fall in 2017 and 2018 years. The experiment was performed at Adaptive Research Farm Sheikhupura. It was laid out in randomized complete block design (RCBD) with four different land preparation techniques including T1= Cultivator (4 times) + Planking (2 times) (Farmer’s Practice), T2=MB plough (1 time) + Disc Harrow (1 time) + Planking (2 Times), T3=MB plough (1 time) + Cultivator (2 times) + Planking (2 Times) and T4= Rotavator (1 time) + Disc Harrow (1 time) + Planking (2 Times), each treatment replicated thrice during both the years. All the other agronomic and crop husbandry operations were kept uniform throughout the growing season every year. The results revealed that preparing land with MB plough (1 time), Disc Harrow (1 time) and Planking (2 times) is the best land preparation method can increase the paddy yield 13.5-17.5% as compared to the traditional method practised by the farmers. Moreover, highest plant height (134.00 cm and 132.00 cm), number of tillers (224 and 220 m-2), number of grains per spike (130 and 116) and 1000-grain weight (23.0 and 22.0 g) respectively during Kharif-18 and Kharif-19 was also recorded in the same treatment. So, preparation of land for paddy in agro-ecological conditions of Sheikhupura using MB plough (1 time), Disc Harrow (1 time) and Planking (2 times) can significantly enhance the paddy yield.

Livelihood diversification strategies and resilience to climate change in semi-arid northern Ghana

Climate change threatens the livelihoods of smallholder farmers in the Global South. In semi-arid northern Ghana, where over 73% of the population is engaged in smallholder agriculture, climate-induced food insecurity is of major concern. Livelihood diversification is acknowledged to have the potential to improve climate resilience in smallholder farming systems through risk spreading. That notwithstanding, little is known about the links between livelihood diversification strategies and climate resilience in such vulnerable settings. Drawing data from a cross-sectional survey with 1100 smallholder households in semi-arid northern Ghana, this study contributes to the literature by examining the association between livelihood diversification and climate change resilience. Findings from logistic regression analysis revealed that smallholder farming households that practiced only farm diversification (OR = 4.66; p ≤ 0.001) and a combination of both farm and nonfarm diversification (OR = 6.28; p ≤ 0.001) had significantly higher odds of reporting stronger resilience to climate change compared to those who did not employ any diversification strategy. The study further revealed that land preparation techniques, source of climate information, and religion were significantly associated with smallholder farmers’ perceived climate change resilience. These findings point to the need for agricultural policy to promote both farm and nonfarm livelihoods as complementary risk-spreading strategies. Exploring the synergies between farm and nonfarm livelihoods may prove beneficial in semi-arid agrarian contexts. In doing so, critical contextual dynamics such as source of farm power and sources of climate information must not be overlooked.

Milkweed Establishment in Restored Central Missouri Prairie

ABSTRACTThe decline of the Eastern North American monarch butterfly (Danaus plexippus) population continues to be a major concern among conservationists. Numerous publications and organizations suggest that establishing milkweed (Asclepias spp.), at a landscape scale, is necessary to increase the monarch population. The translocation of commercially grown containerized plugs is commonly recommended to establish milkweed. During 2017, we used a split‐plot design to examine the factors of age of prairie restoration, plant type, and land preparation method on survival of translocated milkweed in restored prairie in central Missouri, USA. Milkweeds were translocated to 16 0.81‐ha sites, half classified as young (<8 yr) and half as old (>9 yr) prairie restorations. We randomly selected 8 sites to establish bare‐root milkweed seedlings and 8 sites were planted with milkweed seedling plugs. Each site contained paired 0.4‐ha plots. At the plot level we tested 2 land preparation techniques, disking with the application of pre‐emergent herbicide and application of a grass herbicide. Milkweeds were planted at the density of 200 milkweeds/0.40 ha as suggested by the Missouri Monarch and Pollinator Conservation Plan. We conducted a census to determine milkweed survival 2 growing seasons after establishment. Two‐year survival of translocated bare‐root milkweed ( = 0.26, 95% CI = 0.12–0.49) was nearly 5 times greater than that of milkweed seedling plugs ( = 0.05, 95% CI = 0.02–0.13). Milkweed in disked plots had greater survival ( = 0.18, 95% CI = 0.10–0.31) than in plots treated with grass herbicide ( = 0.08, 95% CI = 0.04–0.16). Milkweed survival in older restored prairies ( = 0.07, 95% CI = 0.03–0.18) was lower than that in newer prairie plantings ( = 0.21, 95% CI = 0.09–0.41). Our results suggest translocation of bare‐root milkweed seedlings, combined with disking and application of pre‐emergent herbicide, is the preferred alternative. We suggest translocation of milkweed may be a feasible method of enhancing monarch habitat. However, meeting the challenge of restoring milkweed at recommended densities in established grasslands may be limited if milkweed seedling plugs are used. © 2020 The Wildlife Society.

Quantifying the effects of precipitation, vegetation, and land preparation techniques on runoff and soil erosion in a Loess watershed of China

The combination of land preparation techniques and vegetation could be an effective way to combat soil degradation on vulnerable, steep slopes. Because of the scale of re-vegetation and man-made micro-topographies in regions of hillies and gullies, quantifying the effects of land preparation techniques, precipitation, and vegetation on runoff and soil erosion remains challenging, particularly in semi-arid areas. This study investigated the runoff and erosion characteristics associated with different land preparation techniques (level bench, level ditch, fish-scale pits and adverse-grade tableland) in combination with different tree species (i.e., Caragana microphylla, Pinus tabulaeformis, Armeniaca sibirica, Platycladus orientalis) using network and redundancy analyses (RDA). Network analysis was used to identify the factors (rainfall features, vegetation types, and land preparation techniques) influential in surface runoff and erosion, while RDA was used to focus on the relations between surface runoff, soil erosion, and all of the influencing factors. Our results suggested that land preparation technique could reduce runoff generation on steep slopes, a key process that affects soil loss, although the extent was affected largely by the influence of the combination of the design of the engineering structure and the shape of the vegetation canopy. Our study indicated that Network analysis and RDA are practical methods to quantify the interactions and co-dependencies between rainfall features and other critical factors (vegetation type and ecological engineering) on runoff and soil loss that were difficult to assess previously using classical regression.

Effects of land preparation and plantings of vegetation on soil moisture in a hilly loess catchment in China

AbstractIn the dryland and degraded regions, soil moisture is the primary factor determining ecological restoration. Proper land preparations and vegetation restoration can improve soil moisture and benefit land restoration. Identifying their effects on soil moisture is thus essential for developing suitable management strategies. In this study, four typical land preparation techniques (level ditches, fish‐scale pits, zig terraces, and level benches) and non‐native vegetation types (Prunus armeniaca, Platycladus orientalis, Pinus tabulaeformis, and Caragana microphylla) were planted on a semiarid loess hilly catchment, China. Soil moisture was monitored by a time‐domain reflectometer, and its spatial–temporal variations were analyzed during the 2014–2015 growing seasons. The following results were captured. (a) Soil moisture was highest for the combination of P. orientalis and fish‐scale pits (P. orientalis/fish‐scale pits, 10.37%), followed by P. armeniaca/level ditches (10.23%), P. orientalis/zig terraces (9.67%), C. microphylla/level benches (8.62%), P. tabulaeformis/fish‐scale pits (8.05%), and P. tabulaeformis/zig terraces (7.72%). (b) Fish‐scale pits offered a better rainwater‐harvesting capacity during the rainy months, whereas zig terraces had a higher water retention capacity under extremely dry conditions (as indicated by the temporal soil moisture variation and soil water retention curves). (c) P. tabulaeformis consumed more water than other vegetation types (26.7% lower than that of P. orientalis). (d) Soil moisture in shallower layers (0–80 cm) was more affected by land preparations and was more effected by vegetation types in deeper soil layers (80–180 cm). We thus suggest that fish‐scale pits may be a better choice in wetter regions whereas zig terraces and P. orientalis are more suitable in the driest parts of the Loess Plateau to restore the fragile ecosystems.

Land preparation and vegetation type jointly determine soil conditions after long-term land stabilization measures in a typical hilly catchment, Loess Plateau of China

Land preparation (e.g., leveled ditches, leveled benches, adversely graded tableland, and fish-scale pits) is one of the most effective ecological engineering practices to reduce water erosion in the Loess Plateau, China. Land preparation greatly affects soil physicochemical properties. This study investigated the influence of different land preparation techniques during vegetation restoration on soil conditions, which remained poorly understood to date. Soil samples were collected from depths of 0–10, 10–20, 20–40, 40–60, 60–80, and 80–100 cm, in the typical hilly watershed of Dingxi City, Loess Plateau. Soil bulk density (BD), soil organic matter (SOM), and total nitrogen (TN) were determined for different land preparations and vegetation type combinations. Fractal theory was used to analyze soil particle size distribution (PSD). (1) The effect of land preparation on soil properties and PSD varied with soil depth. For each land preparation category, SOM and TN values showed a significant difference between the top soil layer and the underlying soil depths. (2) The fractal dimension of PSD showed a significant positive correlation with clay and silt content, but a significant negative correlation with sand content. (3) The 20 cm soil layer was a boundary that distinguished the explanatory factors, with land preparation and vegetation type as the controlling factors in the 0–20- and 20–100-cm soil layers, respectively. Land preparation and vegetation type significantly influenced soil properties, with 20 cm soil depth being the boundary for these two factors. This study provided a foundation for developing techniques for vegetation restoration in water-limited ecosystems.

Impacts of Farmers’ Participation in Upscaling Technologies on Mungbean (<i>Vigna radiata</i> L.) Production in the South-Western Region of Bangladesh

The study evaluated the farmers’ participatory methods of upscaling technologies for increasing mungbean production in the south-western region of Bangladesh. It was a descriptive survey study and data were collected by interviewing 120 sample farmers in DFID-Mungbean Project areas in Bangladesh. The participatory methods trailed in the project were farmers seed exchange program, demonstrations trials, agricultural training and workshops on mungbean production. However, farmers to farmers seed exchange program was identified as the most effective method. During the project phase, the farmers selected and adopted their preferred mungbean varieties, developed and practiced appropriate land preparation techniques along with improved post-harvest operations. Farmers’ participation in technology generation and upscaling resulted in increasing area and production of the mungbean many fold during 2004 to 2008. The average yield of mungbean was 1370 kg/ha and almost all framers obtained yields more than that of the national average of 705 kg/ha. Agricultural training, farm size and extension contact accounted for 83% of the total variation in upscaling technology and 90% of the variation in yield of mungbean. The extent of upscaling technology in terms of increase in area and yield of mungbean were associated with various participatory methods practiced by the farmers in the study area. The Agriculturists 2014; 12(2) 39-47

Evaluation of Traditional Plantation Management Techniques with Respect to Modern Concepts of Plantation Management

The traditional Sri Lankans led a simple yet a sustainable life in harmony with the natureutilising its resources wisely and appropriately. Since the vitality of forest resources werewell known, properly designed plantation management techniques were followed by themeven in ancient times. The traditionally practiced plantation management techniques arehighly significant since most of these methods are more or less similar to the plantationmanagement practices which are used in modern plantations leading to a sustainablemanagement of forest resources. These traditional practices are evaluated on a scientific basisalong with the modern concepts of sustainable plantation management to signify the ecoconsciousness of traditional plantation management techniques. Different traditionalplantation management practices were gathered from literary sources such as ancientmanuscripts, palm leave books, publications etc. The gathered methods were verified throughoral interviews with experienced traditional experts and the verified methods werescientifically evaluated and were compared with the basic plantation management conceptspracticed under sustainable plantation management at present. The methods of assessing soilsuitability for various plantations, the specific requirements of floral species, ecofriendly landpreparation techniques (such as phytoremediation etc.), different seeding or plantationmethods (based upon the used floral species), the optimum spaces or gaps that should bemaintained between two trees (for different floral species), plant treatment methods,harvesting ages of different species are discussed in detail within the traditional sourceswhich seem to bear the same core concepts as of the modern techniques. Hence thetraditional plantation management techniques can be defined as the fundamentals ofsustainable forest resources management that have been gradually evolved into modernconcepts of plantation management.

Awareness and effectiveness of vegetable technology information packages by vegetable farmers in Adamawa State, Nigeria

Dry season vegetable production plays a key role in agricultural economics of Adamawa state, as a basic source of food, income and employment especially for resource poor farmers. This study evaluates the awareness and effectiveness of agricultural technology information by dry season vegetable farmers in Mubi region. Findings revealed that the vegetable production is gender sensitive to the male sex. Most household depend on family as a reliable source of labour. Awareness was high for vegetable production information packages. The farmers indicated the need for agricultural extension services, the dearth of which limits achieving high productivity. The use of mechanized land preparation techniques was less effective among the farmers interviewed. Vegetable technology information as seed dressing, availability of improved seeds, planting methods, weeding, water and disease management, pest control, harvesting and use of fertilizer were found to be very effective among the farmers. This could influence positively vegetable production in the study areas. The low effectiveness rating for mechanized land preparation and water management practices may be associated with the complex and expensive nature of these technologies. Key words: Dry season farming, agricultural technology information, complex technology, effectiveness, awareness.

The effect of land preparation at re-establishment on the productivity of fast growing hardwoods in South Africa

Appropriate land preparation at re-establishment is of major importance to forest managers to ensure maximum survival and vigorous early growth of South African plantation forests. This work revisits a series of trials carried out over the last two decades in an attempt to evaluate the long-term effects of land preparation at re-establishment on the productivity of fast—growing hardwoods (Acacia mearnsii and Eucalyptus spp.). A wide range of land preparation techniques was tested: ploughing, ripping, subsoiling, ridging and complete site preparation (de-stumping, ripping and discing) inter alia. Of the eleven trials originally planted, five reached rotation age (between 9 and 11 years) and, apart from one which was destroyed by a storm at 5 years, the rest, at time of writing, were close to clearfelling. With the exception of one trial where significant growth responses were recorded, and apart from a few significant lower-order interactions, final survival, basal area and volume were not affected by land preparation when compared to a standard pitting operation. Overall, growth responses in terms of basal area and volume to various forms of surface cultivation, ripping, subsoiling and terracing ranged between +21% and—23% for all species tested. Intensive site preparation (e.g. de-stumping, ripping/subsoiling and discing) has generally not resulted in improved growth of E. grandis or A. mearnsii across a range of sites and in some cases even resulted in a reduction in site productivity. Erratic growth responses of Eucalyptus spp. and A. mearnsii to ripping were recorded. Forest management should focus efforts on less intensive and more cost-effective methods of re-establishment such as pitting, shallow ripping to mark a planting line, or surface ploughing unless a known growth limitation exists (such as a root-limiting compacted B horizon overlying a horizon with available water). It is conjectured that the lack of major growth responses to intensive site preparation is due to a combination of the good physical condition of forest soils in the summer-rainfall growing region of South Africa, and beneficial perforation effects of tree roots from previous rotations. The results imply that topsoil disturbance and mixing of soil layers caused by intensive site preparation may pose a threat to long-term site productivity.

Hydrology and related changes after harvesting native forest catchments and establishing pinus radiata plantations. Part 3. Stream temperatures

AbstractEight small steep south‐west facing catchments (1‐63‐8‐26 ha) have been monitored in Westland, New Zealand since 1974. Two catchments were retained in native mixed evergreen forest and the rest were subjected to various harvesting and land preparation techniques before being planted with Pinus radiata between 1977 and 1980. Stream temperatures were measured in all catchments for 11 years, including up to four years before harvesting.The streamwater temperature regime under the native forest cover has a seasonal cycle, with an annual mean of about 9°C and mean daily temperatures ranging between a winter minimum of about 5.8°C and a summer maximum of 12.S°C. After harvesting, the winter minimum stream temperatures in all trials were unchanged as topography exerts the major control over incoming solar radiation. The largest rises in mean summer stream temperatures, up to 5.5°C, were in the catchments that had been clearcut and burnt before planting. The maximum stream temperature recorded was 22.8°C in a clearcut catchment with no riparian reserve. Summer stream temperatures in this catchment were up to 11°C higher than in an adjacent control catchment. Summer stream temperature rises in catchments with riparian reserves were less than 1.5°C.Seven years after harvesting, stream temperatures were dropping towards pre‐treatments levels in only two of the six treated catchments as revegetation of the riparian areas occurred and the plantations became established.As these small headwater streams discharge into streams with flows one or two orders of magnitude larger, the increases in summer stream temperatures will be rapidly dissipated. However, the cumulative impact of harvesting many small headwater catchments that discharge into a larger stream could have a noticeable effect on stream temperature if intact riparian reserves were not retained in both headwater and main streams.

Hydrology and related changes after harvesting native forest catchments and establishing pinus radiata plantations. Part 2. The native forest water balance and changes in streamflow after harvesting

AbstractSix small, steep, south‐west facing catchments (1.63–4.62 ha) have been monitored in Westland, New Zealand since 1974. Two catchments were retained in native mixed evergreen forest and the rest were subjected to various harvesting and land preparation techniques before being planted with Pinus radiata between 1977 and 1980.The 11‐year water balance for the native forest catchments was: rain = streamflow + interception loss + transpiration + seepage (2370mm = 1290mm + 620mm + 360mm + 100mm). In the year after treatment streamflow generally increased by 200–250 mm, except for one treatment (clearfelling, herbicide application, no riparian reserve) where the increase was 550 mm. The catchments were planted with Pinus radiata, but rapid colonization by bracken (Pteridium esculentum) and Himalayan honeysuckle (Leycesteria formosa) led to a rapid decline in streamflow, which returned to pre‐treatment levels after an average of about five years. Streamflow yields then continued to decline for another two to three years before stabilizing at a level about 250mm yr−1 lower than pre‐treatment levels. At this time the catchments had a dense bracken/honeysuckle understorey beneath 5 m tall pine trees.

Establishment and early growth after rice of subterranean clover (Trifolium subterraneum), Persian clover (T. resupinatum), balansa clover (T. michelianum), and white clover (T. repens)

Four temperate clovers were grown on a typical rice-growing soil in the Murrumbidgee Valley, New South Wales, to assess their establishment and early growth potential. Subterranean clover (Trifolium subterraneum var. yanninicum) cv. Trikkala, Persian clover (T. resupinatum) cv. Maral, balansa clover (T. michelianum var. balansae) cv. Paradana, and white clover (T. repens) cv. Haifa were sown immediately following a rice crop in autumn of 3 consecutive years. Seven sowing methods were compared, including combinations of surface or drill sowing with land preparation techniques commonly used in rice-farming systems. All cultivars established successfully. Trikkala had the best establishment on the basis of per cent seed sown in year 2, and equal best in years 1 and 3, although Paradana and Maral had higher plant densities at the sowing rates used. Paradana and Maral produced the highest dry matter yields and Haifa the lowest (P<0.05) in the growing period to mid-spring. Sowing method strongly influenced (P<0.05) both establishment and yield of clover. Sowing into a dense rice canopy before harvest severely restricted clover performance, while harvesting rice before sowing greatly improved (P<0.05) clover establishment and dry matter production. Establishment from surface sowing was generally more successful than from drill sowing, although yields with both methods were mostly satisfactory. Establishment and yields were highest after burning stubble, but this effect was variable and not always significant. Sowing after cultivation was not successful, especially in the 2 wetter years, due to poor seedbed preparation and waterlogging.

Tillage Effects on Soil Physical Properties and Wetland Rice Yield

AbstractPuddling is the most common method of land preparation for wetland rice (Oryza sativa L.) in south and southeast Asia. While this method has certain advantages, it is time‐, energy‐, and capitalintensive. The objective of this study was to identify time‐, energy‐, and capital‐efficient tillage techniques for sustained productivity of wetland rice soils. The effects of different land preparation techniques on soil physical properties, root growth, and grain yield of wetland rice (cv. IR36) on two Philippine (IRRI) soils are reported. Bulk density, penetration resistance, and temperature of surface soil layers decreased with tillage intensity. In clay soil (Andaqueptic Haplaquoll with a water table of 0.30 m), the average daily water use (percolation + seepage + evapotranspiration) during a 90‐d irrigation period for zero tillage (dry‐seeded rice) was 37 mm d−1; zero tillage (transplanted rice), 35 mm d−1; minimum tillage, 34 mm d−1; and puddling, 30 mm d−1. The corresponding values for the clay loam (Typic Argiudoll with a water table > 1.2 m) were 393, 501, 263, and 164 mm d−1, respectively. Root‐length density (RLD) at the 0‐ to 0.10‐m depth at harvest was negatively correlated with soil bulk density at transplanting. On the other hand, grain yield was positively correlated with RLD, but negatively correlated with bulk density and soil penetration resistance and was less on zero‐tilled than on tilled plots. For the clay soil, grain yield (two‐season average) with minimum tillage was 26% higher than with zero tillage. for shallow puddling (one‐season data) and puddling, the figures were 33 and 28% higher. The corresponding values in clay loam soil were 36,66, and 56%, respectively. Zero and minimum tillage plots dried faster than puddled plots after they were drained at harvest; surface cracking was higher in puddled plots. In the clay soil and in both seasons, minimum tillage produced the same grain yield as puddling, and in such soil, minimum tillage may be an alternative to puddling, provided weeds are controlled.

Rendimientos de sandía, tomate y gandul en terrenos preparados según distintas técnicas

Se evaluaron tres técnicas diferentes para preparar el terreno para sandías, tomate y gandúl en un suelo de la serie San Antón (del orden de los Mollisol) en la región sur de Puerto Rico. Las diferentes formas de preparar el suelo se compararon con la técnica de sembrar sin labranza. Los tratamientos fueron: 1) sin labranza; 2) labranza mínima (remover el suelo sin voltearlo), 3) labranza convencional (dos cortes de arado a una profundidad de 15 cm cada 2 semanas); 4) labranza profunda (4 cortes de arado a una profundidad de 45 cm cada semana). Cada parcela tratada se dividió en tres, en las que se sembraron los cultivos indicados. Después de cosechar el primer experimento se sembraron otra vez las mismas cosechas en los mismos sitios para medir el efecto residual. No se observaron respuestas estadísticamente significativas de los tratamientos en los cultivos estudiados. En general, la respuesta individual tampoco fue significativa. Los resultados obtenidos sugieren la posibilidad de que estos cultivos puedan sembrarse con labranza mínima y en algunos casos hasta sin labraza, si se establecen en condiciones similares a las que prevalecieron en el estudio que aquí se informa. No se detectaron diferencias significativas entre tratamientos con respecto a resistencia a la penetración, pH y concentración de N, P, K, Ca, Mg. Se registró una reducción substancial an el rendimiento de sandía y tomate cuando el mismo cultivo se sembró en el mismo lugar dos veces consecutivas.